/*
 * CCVisu is a tool for visual graph clustering
 * and general force-directed graph layout.
 * This file is part of CCVisu.
 *
 * Copyright (C) 2005-2011  Dirk Beyer
 *
 * CCVisu is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * CCVisu is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with CCVisu; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Please find the GNU Lesser General Public License in file
 * license_lgpl.txt or http://www.gnu.org/licenses/lgpl.txt
 *
 * Dirk Beyer    (firstname.lastname@uni-passau.de)
 * University of Passau, Bavaria, Germany
 */
package org.sosy_lab.ccvisu.readers;

import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;

import org.sosy_lab.ccvisu.graph.Relation;
import org.sosy_lab.ccvisu.graph.Tuple;
import org.sosy_lab.common.LogManager;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

import com.google.common.collect.ImmutableList;

public class SAXHandlerDOXIndex extends DefaultHandler {

  // COMPOUND kind values: class, struct, union, interface, protocol, category,
  //                       exception, file, namespace, group, page, example, dir
  // MEMBER kind   values: define, property, event, variable, typedef,
  //                       enum, enumvalue, function, signal, prototype,
  //                       friend, dcop, slot

  private enum TagType {
    UNKNOWN, COMPOUND, MEMBER
  };

  private class Entry {
    private final int    level;
    private final String kind;
    private final String id;
    private String       name = "";

    Entry(int level, String kind, String id) {
      assert (level > 0 && kind != null && id != null);
      this.level = level;
      this.kind = kind;
      this.id = id;
    }

    public int getLevel() {
      return level;
    }

    public String getKind() {
      return kind;
    }

    public String getId() {
      return id;
    }

    public String getName() {
      return name;
    }

    public void setName(String name) {
      assert(name != null);
      this.name = name;
    }
  }

  private int              xmlLevel               = 0;
  private TagType          detectingNameOfTagType = TagType.UNKNOWN;
  private Entry            currentCompound        = new Entry(1, "", "");
  private Entry            currentMember          = new Entry(1, "", "");
  private List<String>     xmlFileIds             = new ArrayList<String>();

  private final Relation   relations;
  private final LogManager logger;

  public SAXHandlerDOXIndex(LogManager logger, Relation relations) {
    super();
    assert(logger != null && relations != null);
    this.logger = logger;
    this.relations = relations;
  }

  @Override
  public void startElement(String uri, String localName, String qualifiedName,
      Attributes attributes) throws SAXException {

    assert(qualifiedName != null);
    xmlLevel++;
    detectingNameOfTagType = TagType.UNKNOWN;

    if (qualifiedName.toLowerCase().equals("compound")
        || qualifiedName.toLowerCase().equals("member")) { // COMPOUND and MEMBER

      assert (attributes != null);
      String id = attributes.getValue("refid");
      assert (id != null);
      String kind = attributes.getValue("kind");
      assert (kind != null);

      if (qualifiedName.toLowerCase().equals("compound")) {
        currentCompound = new Entry(xmlLevel, kind, id);
      } else {
        currentMember = new Entry(xmlLevel, kind, id);
      }

    } else if (qualifiedName.toLowerCase().equals("name")) { // NAME
      if (xmlLevel == currentCompound.getLevel() + 1) {
        detectingNameOfTagType = TagType.COMPOUND;
      } else {
        assert (xmlLevel == currentCompound.getLevel() + 2);
        assert (xmlLevel == currentMember.getLevel() + 1);
        detectingNameOfTagType = TagType.MEMBER;
      }
    } else if (qualifiedName.toLowerCase().equals("doxygenindex")) { // DOXYGENINDEX
      // Not needed.
    } else {
      assert (false);
    }
  }

  @Override
  public void endElement(String uri, String localName, String qualifiedName)
      throws SAXException {

    assert(qualifiedName != null);
    detectingNameOfTagType = TagType.UNKNOWN;

    if (qualifiedName.toLowerCase().equals("compound")) { // COMPOUND

      assert (xmlLevel == currentCompound.getLevel());
      if (currentCompound.getName().equals("")) {
        logger.log(Level.SEVERE, "Runtime Error: No name found for compound "
                           + currentCompound.getId() + ".");
        System.exit(1);
      }

      List<String> tuple = new ArrayList<String>();
      tuple.add(currentCompound.getKind());
      tuple.add(currentCompound.getId());
      tuple.add(currentCompound.getName());
      relations.addTuple(new Tuple("COMPOUND", tuple));

    } else if (qualifiedName.toLowerCase().equals("member")) { // MEMBER
      assert (xmlLevel == currentCompound.getLevel() + 1);
      assert (xmlLevel == currentMember.getLevel());

      if (currentMember.name.equals("")) {
        logger.log(Level.SEVERE, "Runtime Error: No name found for member "
            + currentMember.getId() + ".");
        System.exit(1);
      }
      {
        List<String> tuple = new ArrayList<String>(3);
        tuple.add(currentMember.getKind());
        tuple.add(currentMember.getId());
        tuple.add(currentCompound.getName() + "." + currentMember.getName());
        relations.addTuple(new Tuple("MEMBER", tuple));
      }
      {
        List<String> tuple = new ArrayList<String>(2);
        tuple.add(currentMember.getId());
        tuple.add(currentCompound.getId());
        relations.addTuple(new Tuple("CONTAINEDIN", tuple));
      }
    }

    xmlLevel--;
  }

  @Override
  public void characters(char[] chars, int start, int length) throws SAXException {
    String name = new String(chars, start, length);
    if (name.trim().equals("")) {
      return;
    }

    if (detectingNameOfTagType == TagType.COMPOUND) { // COMPOUND name
      xmlFileIds.add(currentCompound.getId());
      // Concatenate the two strings (e.g. "MyClass<T" + ">").
      currentCompound.setName(currentCompound.getName() + name);

    } else if (detectingNameOfTagType == TagType.MEMBER) { // MEMBER name
      // Concatenate the two strings (e.g. "operator" + "<=").
      currentMember.setName(currentMember.getName() + name);
    }
  }

  /**
   * @return       list of file names to process.
   */
  ImmutableList<String> getXmlFileIds() {
    return ImmutableList.copyOf(xmlFileIds);
  }
}
